Electric bell-pull



(No Model.)

L. B. TINKHAM. ELECTRIC BELL PULL.

No. 450,706. Patented Apr. 21, 1891.

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M y 7 r I a UNITED STATES LEMUEL B. TINKHAM, OF

PATENT OFFICE.

BOSTON, MASSACHUSETTS.

ELECTRIC BELL-PU LL.

SPECIFICATION forming part of Letters Patent No. 450,706, dated April 21-, 1891.

I Application filed October 11, 1890. Serial No. 367,816. (No model.)

To all whom it may concern:

Be it known that I, LEMUEL B. TINKHAM, of Boston, county of Snfiolk, State of Massachusetts, have invented certain new and useful Improvements in Electric Bell-Pulls, of which the following is a specification, reference being had to the drawings accompanying and forming a part hereof.

So far as known to me, electric bell-pulls as now made require some special fitting of the shank,which takes time, and which cannot be conveniently done out of the shop.

One of the chief objects of my invent-ion is to obviate this difficulty by supplying an auxiliary piece,which may be applied to the shank of an ordinary bell-pull without altering or fitting the shank, and by the addition of which the bell-pull is made into an electric bell-pull.

Another object of my invention is to produce an inexpensive electric bell-pull of high efficiency and durability, and which is of such simple construction as not to be likely to get out of order easily; and it consists in a bellpull constructed as hereinafter described, and as is more particularly pointed out in the claim which is appended hereto and made a part hereof.

In the accompanying drawings I have shown my invention as embodied in the best form now known to me, and in the following de scription I will refer thereto.

In said drawings, Figure 1 is a plan view of my bell-pull with my improvement attached. Fig. 2 is a vertical lengthwise section, dotted lines being used to show the pull withdrawn. Fig. 3 is amodification. Fig. 4. is another modification.

Ais the knob, 13 the shank, and O the shieldplate, of a bell-pull of common construction.

D is a carriage having a central aperture lengthwise thereof to receive the shank B and in which the shank may slide. The carriage D is cut away on top above the shank, as shown at c, to receive a small roll f, which is of a length slightly less than the width of the opening e. A spring-tongue g is secured at one end to the end of said carriage and projects over the opening e. This spring 9 is so placed that it bears upon the roll f when the roll is under it. Another spring-tongue his secured at the other end of the carriage and projects toward but does not touch the spring g. The spring h is insulated from the carriage by means of the upright strip j, of insulating material, to which its base-plate 7c is secured, as shown. A cap Z, of any suitable construction, is secured to the end of the shank, and a spiral spring on is placed between said cap and the carriage D. This spring tends to throw the bell-pull in and hold it in that position. The electric wires are connected with the binding posts or screws shown atp q. YVhen the pull is in and the rollfis under the spring -g, as shown in Fig. l, the circuit is broken; but when the pull is drawn out the movement of the shank under the roll f causes it to roll to the other end of the opening e and under the spring h. As soon as the roll is under spring h circuit is made through said spring, the roll f, shank D, and carriage, and the bell rings. Vhen the pull is allowed to fly back, the movement is reversed, the roll f moves from under spring h to the other end of opening c under spring g, and the circuit is broken. As will be clear, the carriage D and roll f maybe kept in stock by any bell-hanger and applied, as wanted, to a bell-pull of common form without specially fitting the parts. In applying the carriage the roll f is placed within it through the opening for the shank and allowed to rest on the spring, the carriage being inverted. The shank is then inserted, the spring on put on the shank, and the cap Z secured in place. The bell-pull is then put in position and the electric wires connected, when it is ready for use.

Figs. 3 and a are modifications of my device in which only one of the spring-plates g h is employed, the other spring being reducd to a mere stationary plate or contact-piece. In both said figures the full lines represent the normal position of the parts and the dotted lines represent the position of the parts when the bell-pull is withdrawn and the bell is ringing. In both said figures the movement of the shank B when the pull is withdrawn is toward the left. In Fig. 3 the spring 9 is extended entirely across the opening 6 and is so placed relatively to the roll f that when the pull is in normal position the roll f throws the spring upwardly, as shown in the full lines in the figure. When the shank B is withdrawn, the roll f moves to the other end of the opening e and the spring g is allowed to press on the plate h and make contact therewith. The inward movement of the shank B raises the spring g and breaks the circuit. In Fig. 4 substantially the same arrangement of parts is employed, except that the spring his extended,while the spring 9 is reduced to a stationary plate or contact and the movement of the spring is reversed-that is, the springis raised to make contact whileit is normally down, as shown by the full lines in said figure. When the shankBis Withdrawn,

the roll fis moved to the other end of the opening 6, forcing up the spring h firmly LEMUEL TINKHAM. lVitnesses:

WM. A. MAoLEoD, RoBT. WALLACE. 

